A control system for a marine vessel that includes a drive source and an operator that receives an operation is able to switch a control mode of the drive source without providing an additional operator. An operation received by the operator when the drive source is resting is disabled, and a function of switching a control mode of the drive source is assigned to the operation of the operator that is received when the drive source is resting.

A small planing watercraft includes: a travel electrical component driven for travel of the small planing watercraft; an accessory electrical component provided separately from the travel electrical component; a battery supplying power to the travel electrical component and the accessory electrical component; a sensor detecting a physical quantity corresponding to a level of the battery; and processing circuitry determining, based on a result of detection of the sensor, whether the level of the battery is a predetermined power saving level, and controlling, when it is determined that the level of the battery is the power saving level, operation of the accessory electrical component so that power consumed by the accessory electrical component is less than that before determination.

A small planing watercraft includes: a travel electrical component driven for travel of the small planing watercraft; an accessory electrical component provided separately from the travel electrical component; a battery supplying power to the travel electrical component and the accessory electrical component; a sensor detecting a physical quantity corresponding to a level of the battery; and processing circuitry determining, based on a result of detection of the sensor, whether the level of the battery is a predetermined power saving level, and controlling, when it is determined that the level of the battery is the power saving level, operation of the accessory electrical component so that power consumed by the accessory electrical component is less than that before determination.

A hybrid ship propulsion machine includes an internal-combustion-drive propulsion part, a fixing bracket configured to fix the internal-combustion-drive propulsion part to a ship, an electric propulsion part, an elevating device configured to elevate and lower the electric propulsion part; and an attachment bracket attaching the electric propulsion part and the elevating device to the fixing bracket. The elevating device is configured to elevate and lower the electric propulsion part between a position where a second propeller of the electric propulsion part sinks below a water surface and a position where the second propeller comes out of the water surface.

A hybrid ship propulsion machine includes an internal-combustion-drive propulsion part, a fixing bracket configured to fix the internal-combustion-drive propulsion part to a ship, an electric propulsion part, an elevating device configured to elevate and lower the electric propulsion part; and an attachment bracket attaching the electric propulsion part and the elevating device to the fixing bracket. The elevating device is configured to elevate and lower the electric propulsion part between a position where a second propeller of the electric propulsion part sinks below a water surface and a position where the second propeller comes out of the water surface.

A hybrid ship propulsion machine includes an internal-combustion-drive propulsion part and an electric propulsion part. The electric propulsion part is attached to a first housing part of the internal-combustion-drive propulsion part, and is disposed at a position higher than an anti-cavitation plate of the internal-combustion-drive propulsion part such that a suction port of the electric propulsion part sinks below a water surface during low-speed movement, which is not a planing state of a ship, and the suction port comes out of the water surface during planing of the ship.

A hybrid ship propulsion machine includes an internal-combustion-drive propulsion part and an electric propulsion part. The electric propulsion part is attached to a first housing part of the internal-combustion-drive propulsion part, and is disposed at a position higher than an anti-cavitation plate of the internal-combustion-drive propulsion part such that a suction port of the electric propulsion part sinks below a water surface during low-speed movement, which is not a planing state of a ship, and the suction port comes out of the water surface during planing of the ship.

A hybrid ship propulsion machine includes an internal-combustion-drive propulsion part and an electric propulsion part. The electric propulsion part is attached to a first housing part of the internal-combustion-drive propulsion part, and is disposed at a position higher than an anti-cavitation plate of the internal-combustion-drive propulsion part such that a second propeller of the electric propulsion part sinks below a water surface during low-speed movement, which is not a planing state of a ship, and the second propeller comes out of the water surface during planing of the ship.

A hybrid ship propulsion machine includes an internal-combustion-drive propulsion part and an electric propulsion part. The electric propulsion part is attached to a first housing part of the internal-combustion-drive propulsion part, and is disposed at a position higher than an anti-cavitation plate of the internal-combustion-drive propulsion part such that a second propeller of the electric propulsion part sinks below a water surface during low-speed movement, which is not a planing state of a ship, and the second propeller comes out of the water surface during planing of the ship.

A ship propulsion system provides a first power transmission device that transmits power from an internal combustion engine to a propeller, a second power transmission device that transmits power from an electric motor to a propeller and that is mounted to the hull so as to be able to turn up and down independently from the first power transmission device, an actuator for causing the second power transmission device to turn up and down, and a control device. The control device is configured so as to be able to select a first drive mode in which the internal combustion engine is driven and the electric motor is not driven, and a second drive mode in which the internal combustion engine is not driven and the electric motor is driven. When the first drive mode is selected, the actuator is operated so that the second power transmission device turns up.